<template>
	<view class="content">
		<!-- f1  顶部导航栏 -->
		<view class="nav">
			<!-- 选项卡水平方向滑动，scroll-with-animation是滑动到下一个选项时，有一个延时效果 -->
			<scroll-view class="tab-scroll" scroll-x="true" scroll-with-animation :scroll-left="scrollLeft">
				<view class="tab-scroll_box">
					<!-- 选项卡类别列表 -->
					<view class="tab-scroll_item" v-for=" (item,index) in category" :key="index"
						:class="{'active':isActive==index}" @click="chenked(index)">
						{{item.name}}
					</view>
				</view>
			</scroll-view>
		</view>
		<!-- 选项卡内容轮播滑动显示，current为当前第几个swiper子项 -->
		<swiper @change="change" :current="isActive" class="swiper-content" :style="fullHeight">
			<!-- f2  攻略页面 -->
			<swiper-item class="swiperitem-content">
				<scroll-view scroll-y style="height: 100%;">
					<view class="nav_item">
						<view class="item-content">
							<!-- 1.大卡片部分 -->
							<navigator url="/pages/strategyDetail/strategyDetail">
								<sCard></sCard>
							</navigator>
							<!-- 2.详情列表部分 -->
					  	<sList v-for="item in 3"></sList>
							<!-- 3.没有更多 -->
							<uni-load-more status="noMore" class="load"></uni-load-more>
						</view>
					</view>
				</scroll-view>
			</swiper-item>
			
			<!-- f3  游记页面 -->
			<swiper-item class="swiperitem-content2">
				<scroll-view scroll-y style="height: 100%;">
					<view class="nav_item2">
						<!-- 1.游记组件 -->
							<travels></travels>
					</view>
				</scroll-view>
			</swiper-item>
		</swiper>
	</view>
</template>
<script>
	import sCard from "@/components/sCard/sCard.vue"
	import sList from "@/components/sList/sList.vue"
	import travels from "@/components/travels/travels.vue"

	export default {
		watch: {
			// swiper与上面选项卡联动
			currentindex(newval) {
				this.isActive = newval;
				this.scrollLeft = 0;
				// 滑动swiper后，每个选项距离其父元素最左侧的距离
				for (let i = 0; i < newval - 1; i++) {
					this.scrollLeft += this.category[i].width
				};
			},
		},
		components:{
			travels,
		},
		data() {
			return {
				isActive: 0,
				index: 0,
				currentindex: 0,
				category: [{
						id: 1,
						name: '攻略',
					},
					{
						id: 2,
						name: '游记',
					},
				],
				contentScrollW: 0, // 导航区宽度
				scrollLeft: 0, // 横向滚动条位置
				fullHeight: "",
			}
		},
		mounted() {
			var that = this;
			//获取手机屏幕的高度，让其等于swiper的高度，从而使屏幕充满
			uni.getSystemInfo({
				success: function(res) {
					that.fullHeight = "height:" + res.windowHeight + "px";
				}
			});
			// 获取标题区域宽度，和每个子元素节点的宽度
			this.getScrollW()
		},
		methods: {
			// 获取标题区域宽度，和每个子元素节点的宽度以及元素距离左边栏的距离
			getScrollW() {
				const query = uni.createSelectorQuery().in(this);
				query.select('.tab-scroll').boundingClientRect(data => {
					// 拿到 scroll-view 组件宽度
					this.contentScrollW = data.width
				}).exec();
				query.selectAll('.tab-scroll_item').boundingClientRect(data => {
					let dataLen = data.length;
					for (let i = 0; i < dataLen; i++) {
						//  scroll-view 子元素组件距离左边栏的距离
						this.category[i].left = data[i].left;
						//  scroll-view 子元素组件宽度
						this.category[i].width = data[i].width
					}
				}).exec()
			},
			// 当前点击子元素靠左留一个选项展示，子元素宽度不相同也可实现
			chenked(index) {
				this.isActive = index;
				this.scrollLeft = 0;
				for (let i = 0; i < index - 1; i++) {
					this.scrollLeft += this.category[i].width
				};
			},
			// swiper滑动时，获取其索引，也就是第几个
			change(e) {
				const {
					current
				} = e.detail;
				this.currentindex = current;
			},
		}
	}
</script>
<style lang="scss">
	.load{
		margin: 40rpx auto;
	}
	page {
		height: 100%;
		display: flex;
	}

	.content {
		background-color: #f6f6f6;
		width: 100%;

		.nav {
			background-color: #fff;
			width: 100%;
			align-items: center;
			height: 90rpx;

			.tab-scroll {
				flex: 1;
				box-sizing: border-box;
				padding-left: 30rpx;
				padding-right: 30rpx;

				.tab-scroll_box {
					padding-bottom: 15px;

					.tab-scroll_item {
						line-height: 60rpx;
						margin: 0 auto;
						padding-bottom: 10px;
						font-size: 16px;
						padding-top: 10px;
					}
				}
			}
		}

		.swiper-content {

			.swiperitem-content {
				width: 720rpx;
				margin: 0 auto;
				background-color: #f6f6f6;
				display: flex;
				flex-direction: column;

				.nav_item {

					justify-content: center;
					
					.item-content{
							display: flex;
							flex-direction: column;
					}
				}
			}
			
			.swiperitem-content2{
				
				.nav_item2{
					display: flex;
			  	flex-direction: column;
					
					.travels{
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
					}
				}
			}
			
			
		}
	}

	.active {
		position: relative;
		color: #3E64FF;
	}

	.active::after {
		content: "";
		position: absolute;
		width: 65rpx;
		height: 8rpx;
		background-color: #3E64FF;
		left: 0px;
		right: 0px;
		bottom: 0px;
		margin: auto;
	}

	/* 隐藏滚动条，但依旧具备可以滚动的功能 */
	/deep/.uni-scroll-view::-webkit-scrollbar {
		display: none
	}
</style>
